From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756539Ab1CBSIj (ORCPT ); Wed, 2 Mar 2011 13:08:39 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:42978 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755636Ab1CBSIi (ORCPT ); Wed, 2 Mar 2011 13:08:38 -0500 Date: Wed, 2 Mar 2011 19:08:27 +0100 From: Ingo Molnar To: Tejun Heo Cc: Yinghai Lu , Ingo Molnar , "H. Peter Anvin" , Thomas Gleixner , linux-kernel@vger.kernel.org Subject: Re: [RFC] Reverting NUMA-affine page table allocation Message-ID: <20110302180827.GA13693@elte.hu> References: <20110226143730.GA26864@htj.dyndns.org> <20110302161900.GP3319@htj.dyndns.org> <20110302170702.GS3319@htj.dyndns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110302170702.GS3319@htj.dyndns.org> User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.3.1 -2.0 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Tejun Heo wrote: > Hello, > > On Wed, Mar 02, 2011 at 08:47:54AM -0800, Yinghai Lu wrote: > > > > Yeah, it's a pretty interesting piece of code in need of some cleanup. > > No, i mean second one is not causing any problem. > > > > that only take end is intentionally. that will make sure we can get > > space for page table even in extreme case. > > Hmmm... it seems like it only took @end because it always allocated > the whole page table in one go. Always from the bottom to top. Am I > missing something? > > > > > If you're interested in doing the above, please go ahead and let me > > > > know. > > > > No. please don't revert it. > > > > Ingo, please get patches that will align to 1G ... from > > > > git://git.kernel.org/pub/scm/linux/kernel/git/yinghai/linux-2.6-yinghai.git memblock > > If you were gonna do that, you could have just said that you objected > to the reverting. The message was Request for Comments - soliciting > responses. > > As I wrote multiple times, I think the code as implemented is a bit > heavy handed for the problem. And a bigger problem for me is that it > kind of just piles on the existing messiness and worsens it. I really > hope we wouldn't be doing that anymore. > > I tried to clean up the page table allocation code but the necessary > changes felt a bit too large at this stage, so IMO that's best left to > the next cycle. Do you plan to implement it more cleanly? > To me, it seems complicated for not good enough reasons. I'll defer > the decision to x86 maintainers. Ingo, hpa, Thomas, what do you guys > think? Would be nice to see an actual patch that does the revert. Thanks, Ingo